1. Field of the Invention
The present invention Relates to a process for producing optically active cyclopropanecarboxylic acid esters.
2. Description of Related Arts
The optically active cyclopropanecarboxylic acid esters are important compounds as intermediates for pharmaceuticals and pesticides. For example, (+)-2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylic acid, also known as chrysanthemum-monocarboxylic acid, constitutes the acid component of synthetic pyrethroid insecticides.
Conventionally, asthemethods for directly producing optically active cyclopropanecarboxylic acid esters by synthetic technique, for example, a method has been known in which a prochiral olefin is reacted with a diazoacetic acid ester in the presence of an asymmetric copper complex using an optically active bis [2-(4,5-diphenyl-1,3-oxazolinyl)]methane as the ligand (Tetrahedron Lett., 32, 7373 (1991)).
Since, however, this method has problems in that the raw material used for synthesizing the ligand is expensive and the method for synthesizing the ligand is complicated, this method can not always be said to be an industrially advantageous.
The present inventors have completed the present invention as a result of an extensive study conducted for the purpose of developing a process for producing optically active cyclopropanecarboxylic acid esters in the presence of a copper complex which is obtainable by reacting a copper compound with a bisoxazoline compound as the ligand which is produced by a simple process from an inexpensive optically active amino acid.